1. Technical Field
The present invention relates to a wavelength conversion element, a light source device, and a projector.
2. Related Art
In recent years, regarding the improvement in performance of a projector, there has been known a device provided with a laser source and a fluorescent material layer, which is exited by the laser beam emitted by the laser source to thereby emit fluorescence light, as a light source device with a wide color gamut and high efficiency (see, e.g., JP-A-2011-53320).
Incidentally, since the fluorescent material layer with a large film thickness has a poor heat rejection property, the temperature of the fluorescent material layer rises as the light intensity of the excitation light is increased. Further, there might arise the problem that the phenomenon called thermal quenching occurs to thereby degrade the luminous efficiency. However, in the related art described above, although the condition in which high luminous efficiency can be obtained is defined by the weight rate of the phosphor, the degradation of the luminous efficiency due to the thermal quenching described above is not considered, and therefore, it is difficult to say that the high luminous efficiency can be obtained in the entire range.